WiGig wireless devices operate in accordance with a Wireless Gigabit (WiGig) specification that is a wireless communication standard of a frequency band of 60 GHz, that is, a millimeter-wave band. The WiGig specification is defined by the Wireless Gigabit Alliance. The communication distance of WiGig wireless devices is short, for example, about 10 m, but WiGig wireless devices can communicate a large capacity of data at high-speeds.
In order to design a wireless communication device (for example, the WiGig wireless device) or to test an operation of a wireless communication device, it is necessary to understand antenna radiation patterns, that is, radiation patterns of radio waves, by using an actual wireless communication device, for performance improvement.
In the related art, in order to measure the antenna radiation pattern of a WiGig wireless device, the WiGig wireless device is brought into an anechoic chamber and the antenna radiation pattern thereof is measured. If the antenna radiation pattern is measured in an environment other than an anechoic chamber, reflected waves are generated from objects in the vicinity of the WiGig wireless device. In particular, in short-range communication, a distinction between a direct wave and the reflected waves is difficult because a time difference between the direct wave and the reflected waves which are to be detected is small, such that it is difficult to measure a correct antenna radiation pattern.
For example, PTL 1 discloses a radio wave environment measuring device which can detect a radio wave condition in an environment other than an anechoic chamber, in which the direct wave and the reflected wave are mixed. In PTL 1, the direct wave and the reflected waves can be separated by a pulse compression technology.
In the pulse compression technology, a reception side which receives a wireless signal detects a correlation between a reception pulse and a reference pulse. A time width of a pulse to be detected can be compressed to a narrower range than the pulse width of a pulse signal that is actually transmitted, and time resolution is improved. In other words, the radio wave environment measuring device disclosed in PTL 1 can separately detect the direct wave and the reflected waves, which have a small time difference from each other.